fix: surface SIP_NO_FILL warnings and prevent silent fund failures

- execution.py: dual-write SIP_NO_FILL and SIP_PARTIAL to engine_event
  so the strategy summary can surface them to users
- execution.py: emit SIP_NO_FILL event (with cash/required amounts) on
  the paper path instead of silently returning when funds are insufficient
- strategy_service.py: improve insufficient_funds message to show exact
  shortfall and reassure user that next SIP will auto-execute when funded
- strategy_service.py: clear SIP_NO_FILL warning after a successful
  SIP_TRIGGERED so it does not persist after funds are added
- runner.py: always write PRICE_FETCH_ERROR and HISTORY_LOAD_ERROR to
  engine_event regardless of ENGINE_DEBUG flag
- db.py (backend + engine): raise default pool sizes to 20/50 max
  connections to handle 100 concurrent users without pool exhaustion

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/app/services/db.py

@@ -94,8 +94,8 @@ def get_database_url(cfg: dict[str, str | int] | None = None) -> str:
 
 def _create_engine() -> Engine:
     cfg = _db_config()
-    pool_size = int(os.getenv("DB_POOL_SIZE", os.getenv("DB_POOL_MIN", "5")))
+    pool_size = int(os.getenv("DB_POOL_SIZE", os.getenv("DB_POOL_MIN", "20")))
-    max_overflow = int(os.getenv("DB_POOL_MAX", "10"))
+    max_overflow = int(os.getenv("DB_POOL_MAX", "30"))
     pool_timeout = int(os.getenv("DB_POOL_TIMEOUT", "30"))
     engine = create_engine(
         get_database_url(cfg),

backend/app/services/strategy_service.py

@@ -1093,12 +1093,23 @@ def _issue_message(event: str, message: str | None, data: dict | None, meta: dic
 
     if event == "SIP_NO_FILL":
         if reason_key == "insufficient_funds":
-            return "Insufficient funds for this SIP."
+            cash = payload.get("cash")
+            required = payload.get("required")
+            if cash is not None and required is not None:
+                shortfall = float(required) - float(cash)
+                return (
+                    f"Insufficient funds — ₹{shortfall:,.0f} short for this SIP. "
+                    "Add funds and the next SIP will execute automatically."
+                )
+            return (
+                "Insufficient funds for this SIP. "
+                "Add funds and the next SIP will execute automatically."
+            )
         if reason_key == "broker_auth_expired":
             return "Broker session expired. Reconnect broker."
         if reason_key == "no_fill":
-            return "Order was not filled."
+            return "Order was not filled. The strategy will retry at the next interval."
-        return f"SIP not executed: {_humanize_reason(reason) or 'Unknown reason'}."
+        return f"SIP not executed: {_humanize_reason(reason) or 'Unknown reason'}. The strategy will retry automatically."
 
     if event == "BROKER_AUTH_EXPIRED":
         return "Broker session expired. Reconnect broker."
@@ -1238,10 +1249,15 @@ def get_strategy_summary(user_id: str):
                         'ORDER_REJECTED',
                         'ORDER_CANCELLED'
                       )
+                      AND ts > COALESCE(
+                        (SELECT MAX(ts) FROM engine_event
+                         WHERE user_id = %s AND run_id = %s AND event = 'SIP_TRIGGERED'),
+                        '1900-01-01'::timestamptz
+                      )
                     ORDER BY ts DESC
                     LIMIT 1
                     """,
-                    (user_id, run_id),
+                    (user_id, run_id, user_id, run_id),
                 )
                 issue_row = cur.fetchone()
 

indian_paper_trading_strategy/engine/db.py

@@ -53,8 +53,8 @@ def _db_config():
 def _init_pool():
     config = _db_config()
     config = {k: v for k, v in config.items() if v is not None}
-    minconn = int(os.getenv("DB_POOL_MIN", "1"))
+    minconn = int(os.getenv("DB_POOL_MIN", "2"))
-    maxconn = int(os.getenv("DB_POOL_MAX", "10"))
+    maxconn = int(os.getenv("DB_POOL_MAX", "50"))
     if "dsn" in config:
         return pool.ThreadedConnectionPool(minconn, maxconn, dsn=config["dsn"])
     return pool.ThreadedConnectionPool(minconn, maxconn, **config)

indian_paper_trading_strategy/engine/execution.py

@@ -371,6 +371,9 @@ def _record_reconciliation_event(cur, event: str, *, logical_time, payload: dict
         return
     if event in {"SIP_EXECUTED", "SIP_PARTIAL", "SIP_NO_FILL", "ORDER_RECONCILIATION_PENDING"}:
         log_event(event, payload, cur=cur, ts=ts, logical_time=logical_time)
+        # Dual-write warning events to engine_event so the strategy summary can surface them
+        if event in {"SIP_NO_FILL", "SIP_PARTIAL"}:
+            insert_engine_event(cur, event, data=payload, ts=ts)
         return
     insert_engine_event(cur, event, data=payload, ts=ts)
 
@@ -680,6 +683,14 @@ def _try_execute_sip_paper(
         funds = broker.get_funds(cur=cur)
         cash = funds.get("cash")
         if cash is not None and float(cash) < sip_amount_val:
+            if not event_exists("SIP_NO_FILL", logical_time, cur=cur):
+                _payload = {
+                    "reason": "insufficient_funds",
+                    "cash": float(cash),
+                    "required": sip_amount_val,
+                }
+                log_event("SIP_NO_FILL", _payload, cur=cur, ts=event_ts, logical_time=logical_time)
+                insert_engine_event(cur, "SIP_NO_FILL", data=_payload, ts=event_ts)
             return state, False
 
         log_event(

indian_paper_trading_strategy/engine/runner.py

@@ -533,6 +533,7 @@ def _engine_loop(config, stop_event: threading.Event):
                 _pause_for_auth_expiry(scope_user, scope_run, str(exc), emit_event_cb=emit_event_cb)
                 break
             except Exception as exc:
+                log_event("PRICE_FETCH_ERROR", {"error": str(exc)})
                 debug_event("PRICE_FETCH_ERROR", "live price fetch failed", {"error": str(exc)})
                 if not sleep_with_heartbeat(30, stop_event, scope_user, scope_run, owner_id):
                     exit_reason = "LEASE_LOST"
@@ -556,6 +557,7 @@ def _engine_loop(config, stop_event: threading.Event):
                 _pause_for_auth_expiry(scope_user, scope_run, str(exc), emit_event_cb=emit_event_cb)
                 break
             except Exception as exc:
+                log_event("HISTORY_LOAD_ERROR", {"error": str(exc)})
                 debug_event("HISTORY_LOAD_ERROR", "history load failed", {"error": str(exc)})
                 if not sleep_with_heartbeat(30, stop_event, scope_user, scope_run, owner_id):
                     exit_reason = "LEASE_LOST"